status of arpege / aladin physics f.bouyssel m é t é o-france

Status of ARPEGE / ALADIN physicsStatus of ARPEGE / ALADIN physics

F.BouysselF.Bouyssel

Météo-FranceMétéo-France

Mesoscale physics and diagnostics tools 12-13/12/2005

PresentationPresentation

1.1.Operational physics Operational physics

2.2.Known problemsKnown problems

3.3.Current developmentsCurrent developments

Operational physicsOperational physics

ARPEGE (global) and ALADIN (LAM) modelsARPEGE (global) and ALADIN (LAM) models

ARPEGE : Global spectral model with stretchedresolution 23 to 130 km, 41 levels (1 hPa), 982s,4 runs/day, 4D-Var (T107, T149) : 6h assimilation cycle

ALADIN : LAM, coupled with ARPEGE~ 10 km, ~ 41 levels (1 hPa), ~ 450sDynamical adaptation or 3D-Var

Others operational configurations : ARPEGE Tropics and ALADIN models

Numerical weather predictionNumerical weather prediction

Climat simulationsClimat simulationsARPEGE-Climat : ~ 250 kmALADIN-Climat : ~ 50 and 20 km

Same dynamics: H, 2SLSI

Physics in ARPEGE/ALADIN PNT-CLIMATPhysics in ARPEGE/ALADIN PNT-CLIMAT

SURFACESURFACEISBA (Noilhan and Planton 89, Mahfouf and Noilhan 96, Giard and ISBA (Noilhan and Planton 89, Mahfouf and Noilhan 96, Giard and Bazile, 2000)Bazile, 2000)2/4 layers force restore scheme (T,W,Wg), bare ground and 2/4 layers force restore scheme (T,W,Wg), bare ground and vegetation fraction, 1 layer snow scheme with pronostic albedovegetation fraction, 1 layer snow scheme with pronostic albedo

RADIATIONRADIATION (2 schemes) (2 schemes)1) ACRANEB (Geleyn and Hollingsworth 79, Ritter and Geleyn 92) : 1) ACRANEB (Geleyn and Hollingsworth 79, Ritter and Geleyn 92) : every time stepevery time step2) FMR15 (Fouquart and Bonnel 80, Morcrette 93) : every 1h or 3h2) FMR15 (Fouquart and Bonnel 80, Morcrette 93) : every 1h or 3hTegen aerosols, UGAMP ozone climatologyTegen aerosols, UGAMP ozone climatologyRandow maximum overlap assumptionRandow maximum overlap assumption

MOUNTAIN DRAGMOUNTAIN DRAG

linear and « form » drag , anisotropy, resonance, « lift » effectlinear and « form » drag , anisotropy, resonance, « lift » effect

important modifications (Geleyn et al., Catry et al. submitted)important modifications (Geleyn et al., Catry et al. submitted)

Physics in ARPEGE/ALADIN PNT-CLIMATPhysics in ARPEGE/ALADIN PNT-CLIMAT

TURBULENT VERTICAL DIFFUSIONTURBULENT VERTICAL DIFFUSION : 2 schemes: 2 schemes

1) 1st order K diffusion scheme (Louis et al. 81) + modifs in stable case +1) 1st order K diffusion scheme (Louis et al. 81) + modifs in stable case +

interactive mixing lengths, shallow convection (Geleyn 87), anti-interactive mixing lengths, shallow convection (Geleyn 87), anti-

fibrillation (Bénard et al. 00)fibrillation (Bénard et al. 00)

2) TKE diagnostic (Mellor/ Yamada 2.0) + « moist » (« F0/F1/F2 » de 2) TKE diagnostic (Mellor/ Yamada 2.0) + « moist » (« F0/F1/F2 » de

Bougeault)Bougeault)

LARGE SCALE PRECIPITATION AND CLOUDSLARGE SCALE PRECIPITATION AND CLOUDS : 2 diagnostic schemes: 2 diagnostic schemes

1) revised Kessler type (evaporation, melting, freezing), cloud 1) revised Kessler type (evaporation, melting, freezing), cloud

condensates diagnosed with RHc and buoyancy, cloudiness with condensates diagnosed with RHc and buoyancy, cloudiness with

Xu&Randall (96) formulationXu&Randall (96) formulation

2) Ricard-Royer statistical scheme2) Ricard-Royer statistical scheme

SUBGRID PRECIPITATION AND CLOUDSSUBGRID PRECIPITATION AND CLOUDSMass flux scheme with a Kuo-type closure (Bougeault 85), vertical Mass flux scheme with a Kuo-type closure (Bougeault 85), vertical

transport of horizontal momentum, vertically varying detrainment and transport of horizontal momentum, vertically varying detrainment and

entrainments rates, downdrafts (Ducrocq and Bougeault 95), etc.entrainments rates, downdrafts (Ducrocq and Bougeault 95), etc.

Known problemsKnown problems

Known problemsKnown problems** Diagnostic schemes for precipitation and clouds Diagnostic schemes for precipitation and clouds

(no microphyics) : lack of more physical relations (no microphyics) : lack of more physical relations between clouds and precipitationsbetween clouds and precipitations

** Overestimation of small rainfall events ( < 3 Overestimation of small rainfall events ( < 3 mm/day) particularly in the Tropics but also in mm/day) particularly in the Tropics but also in mid-latitudes (more sophisticated microphysics, mid-latitudes (more sophisticated microphysics, triggering of convection, ...)triggering of convection, ...)


** Overestimation of precipitation over mountains Overestimation of precipitation over mountains (envelop orography, diagnostic RR schemes, (envelop orography, diagnostic RR schemes, moisture convergence)moisture convergence)

ALADIN ARPEGE

RR error using raingauges (JAS 2005)

** Underestimation of low level clouds (turbulence Underestimation of low level clouds (turbulence with cloud top entrainment, microphysics, shallow with cloud top entrainment, microphysics, shallow convection)convection)


TOP SW : MODEL – CERES (DJF)

** Diurnal cycle of Diurnal cycle of convection convection

** Problem of transition Problem of transition between shallow and between shallow and deep convection deep convection

** Lack of moist Lack of moist convection in case of no convection in case of no synoptic forcing synoptic forcing (moisture convergence (moisture convergence only)only)

** Top of convection at Top of convection at neutral levelneutral level

(Guichard et al., 2004)(Guichard et al., 2004)


MESO-NHMESO-NH ARPEGEARPEGE

Q2Q2

25%,25%, 50%,50%, 70% 70% oror 90% 90% relative relative humidityhumidity

** Lack of sensitivity to humidity Lack of sensitivity to humidity environmentenvironment


(Piriou, 2005)(Piriou, 2005)

Current developmentsCurrent developments

Current developmentsCurrent developments

All problems presented before are common to all All problems presented before are common to all ARPEGE/ALADIN - PNT or Climat modelsARPEGE/ALADIN - PNT or Climat models

Convergence of NWP and Climat ARPEGE/ALADIN physics Convergence of NWP and Climat ARPEGE/ALADIN physics towards more sophisticated physical parametrisarions for towards more sophisticated physical parametrisarions for resolutions above 10km with a maximum of synergy with resolutions above 10km with a maximum of synergy with finer scale physics when possible!finer scale physics when possible!

MICROPHYSICSMICROPHYSICS

qv

ql

qi

qr

qs

condensationevaporation

autoconversioncollection

autoconversioncollection

fall

fall

evaporation

sublimation

melting

Original scheme : Lopez, 2001

MICROPHYSICSMICROPHYSICS

Cloud statistical scheme with triangular PDF: Smith, 90Dependency of with x and

Separation of qc in ql, qi function of temperatureKessler type autoconversion (threshold and rate funtion of T)

Specification of hydrometeor distributions for coll., evap., subl. :Concentration : N(D) = N0exp(-D) (Marshall-Palmer)Mass: M(D)=D

Fall velocity: V(D)=D

Precipitation sedimentation : semi-lagrangien conservative schemaConstant fall speed for snow and rain (0.9 and 5 m/s)

Case study : 09/12/2004Case study : 09/12/2004

Austrian alpin case (9 december 2000)

Oper

Observations (from ZAMG)

New

(Haiden and(Haiden and

Wittman)Wittman)

oper Lopez

Lopez no advection of qrLopez no advection of ql, qi and qrImpact of advection

Operational at ECMWF and used in MESO-NH and AROMEOperational at ECMWF and used in MESO-NH and AROME

Rayonnement thermique : RRTM (Mlawer et al., 97)(Morcrette Rayonnement thermique : RRTM (Mlawer et al., 97)(Morcrette et al.,98)et al.,98)

Rayonnement solaire : (Fouquart and Bonnel, 80)(Morcrette,93)Rayonnement solaire : (Fouquart and Bonnel, 80)(Morcrette,93)

Maximum randow overlap assumptionMaximum randow overlap assumption

Cloud optical properties :Cloud optical properties :liquid water cloud : SW / Fouquart (87), LW / Smith-Shi (92)liquid water cloud : SW / Fouquart (87), LW / Smith-Shi (92)ice water cloud : SW / Ebert-Curry (92), LW / Smith-Shi (92)ice water cloud : SW / Ebert-Curry (92), LW / Smith-Shi (92)

Coud effective radius :Coud effective radius :liquid water cloud : Martin et al. (94)liquid water cloud : Martin et al. (94)ice water cloud : Sun et al. (01)ice water cloud : Sun et al. (01)

RADIATIONRADIATION

TEST-SUITE (july-nov 05)TEST-SUITE (july-nov 05)

- Pronostic microphysics + RRTM/SW6 radiation + vertical - Pronostic microphysics + RRTM/SW6 radiation + vertical diffusion of cloud conservative variables (qt, sl)diffusion of cloud conservative variables (qt, sl)

- Remove biais of RS + more EARS data and SATOB data- Remove biais of RS + more EARS data and SATOB data- New climatological files- New climatological files

Improvment in ARPEGE and ALADIN forecasts on cloud, Improvment in ARPEGE and ALADIN forecasts on cloud, precipitation and wind fieldsprecipitation and wind fields

BUTBUTDegradation of geopotentiel scores after 60h forecast over Degradation of geopotentiel scores after 60h forecast over

Europe in assimilation mode but not in forecast one!Europe in assimilation mode but not in forecast one!

Problem of microphysics tunings linked with stretched grid?Problem of microphysics tunings linked with stretched grid?Degradation of linear tangent approximation?Degradation of linear tangent approximation?Problem with obs modifications linked with bias?Problem with obs modifications linked with bias?

DJF - AMIP (forced) Mean Sea Level Pressure (hPa)

MOUNTAIN DRAGMOUNTAIN DRAG

(Déqué)

OPER NEW

SURFEX (externalized surface)SURFEX (externalized surface)

Vegetation and soil : ISBA(Interface Soil Biosphere Atmosphere)

Town : TEB(Town Energy Balance)

Lakes :prescribed temperature, Charnock formula

Sea and ocean :prescribed SST, Charnock formula will soon include a better bulk formulation reflexion to implement a 1D oceanic mixing layer

ISBA physicsISBA physicsSoil options: Force restore, 2 layers , temp, water, ice

Force restore, 3 layers , temp, water, iceDiffusion, N layers , temp, water, ice

Vegetation options:Noilhan and Planton 89 (~Jarvis)AGS (photsynthesis and CO2 exchanges)AGS and iteractive vegetation

Hydrology options:no subgrid processsubgrid runoff, subgrid drainage

Snow options:Douville 95 (1 layer, varying albedo, varying density )Boone and Etchevers 2000 (3 layers, albedo, density, liquid water in snow pack)

Tiling : 1 to 12 patches

TURBULENT VERTICAL DIFFUSIONTURBULENT VERTICAL DIFFUSION

l

ec

z

ewPP

t

e TTd

T2/3'

22

'''' )()(z

v

z

uel

z

vvw

z

uuwP Tud

)()()( ''''''ltqvl

vl

wEqwEwg

P Moist variables

3'' )(

z

qelqw t

Tut 3'' )(

z

elw lTul

Redelsperger and Sommeria( 81),Bougeault (82) and Bechtold (93)

TKE-l Cuxart et al (2000)

z

eel

zz

ew TTue

T '

Diffusion :

z

eel

z

ew TT

T

2

'

In Hirlam :

Mixing length :

with 4.0 ue

2/33/23/2

2

1downup ll

Bougeault and Lacarrère (89) 2/1

downupll

dwup lll

111with

now

2*

2* 3.075.3 wue ClsT

CONVECTIONCONVECTION

• Modifications around current scheme Modifications around current scheme using CAPE for CVNP and CVP (Gueremy)using CAPE for CVNP and CVP (Gueremy)

• Proposition of equationsProposition of equations « MT-CCF » « MT-CCF » for for developing convective parametrizationsdeveloping convective parametrizations

Move the parametrization effort Move the parametrization effort from detrainment towards from detrainment towards microphysics.microphysics.

Continuity : CV dry Continuity : CV dry CVNP CVNP CVP CVP

Easier validation with CRMEasier validation with CRM

(Gerard, Piriou, Geleyn, Stiperski)(Gerard, Piriou, Geleyn, Stiperski)

2 works :

CRM CRM MNHMNH

ARPEGEARPEGEnewnew

ARPEGEARPEGEoperoper

(Piriou, 05)

Low clouds (1000-680hPa) mean JJA : EXP - ISCCP

ARPEGE climatreference

ARPEGE climatTKE pron. (CBR)

with top PBL entraînement Microphys pron.

CVPP+CVP (CAPE)

(Marquet & Gueremy)

CONCLUSIONCONCLUSION

• Common physics for >10km (PNT Common physics for >10km (PNT and Climat)and Climat)

• Lot of common points with finer Lot of common points with finer scale physics (surface, radiation, scale physics (surface, radiation, turbulence, convection ?). turbulence, convection ?). Potentially important for coupling.Potentially important for coupling.

• Need common phys/dyn interface Need common phys/dyn interface and diagnostics for large and diagnostics for large collaboration (cross validation, collaboration (cross validation, etc ...)etc ...)

status of arpege / aladin physics f.bouyssel m é t é o-france

Documents